Adaptive Immunity

Question 1

What are the 3 main functions of the lymphatic system?

Answer 1

• drainage of tissue
• absorption and transport of fatty acids and fats
• immunity

Question 2

Where does the ‘recognition’ phase in the adaptive immune response take place?

Answer 2

secondary lymphoid organs

Question 3

What are the secondary lymphoid organs?

Answer 3

lymph nodes, the spleen and mucosal associated lymphoid tissue

Question 4

What are the primary lymphoid organs?

Answer 4

bone marrow and thymus

Question 5

What happens in primary lymphoid tissue?

Answer 5

blood cells are produced and receive their early training

Question 6

What happens at the thymus?

Answer 6

maturation of T cells that were generated in the bone marrow

Question 7

What happens at the secondary lymphoid organs?

Answer 7

activation of lymphocytes by antigens

Question 8

What does the spleen do?

Answer 8

filters blood of antigens, defective or worn out blood cells and microorganisms and contains many kinds of blood cells

Question 9

What is a major feature of all secondary lymphoid organs except the spleen?

Answer 9

high endothelial venules

Question 10

What is meant by ‘high endothelial venules’?

Answer 10

‘doorway’ through which B and T cells enter the secondary lymphoid organs from the blood - essentially gaps between endothelial cells

Question 11

What is an example of mucosal-associated lymphoid tissue?

Answer 11

Peyer’s patches

Question 12

How do some lymphocytes become memory cells?

Answer 12

stimulation of naive lymphocytes by exposure to antigen

Question 13

Where are B cells produced?

Answer 13

bone marrow

Question 14

What do B cells mature into?

Answer 14

plasma cells

Question 15

What do plasma cells do?

Answer 15

produce antibodies

Question 16

What do B cells express?

Answer 16

surface immuoglobulin which is the antigen receptor for the B cell

Question 17

Why is it more important to make T cells tolerant than B cells?

Answer 17

B cells cannot make antibodies without the help of T cells

Question 18

What is an antigen?

Answer 18

any substance capable of triggering an immune response

Question 19

What structures on antigens characterise the antigens to immune cells as being foreign?

Answer 19

epitopes which protrude from its surface

Question 20

What are the basic features of an antibody (structurally)?

Answer 20

• made up of a heavy and a light chain
• has Fc region (stem bit)
• Y shaped

Question 21

What are the 2 types of antibody light chain?

Answer 21

lambda and kappa and they have no effect on Ig class

Question 22

What do heavy chains on antibodies define?

Answer 22

class of Ig

Question 23

How many different classes of antibody are there?

Answer 23

5

Question 24

What are the 5 classes of antibody and what is their function?

Answer 24

IgM - good at fixing complement and opsonisation
IgG- good opsoniser
IgA- protects mucosal surfaces, resistant to stomach acid
IgE- defends against parasites, causes anaphylactic shock and allergies
IgD- no known Ab function

Question 25

What are the 2 ways B cells can be activated to produce antibodies?

Answer 25

• with T cell help

- without T cell help

Question 26

What does T cell independent activation require?

Answer 26

huge numbers of B Cell Receptors to be clustered together by an antigen with a large number of repeated epitopes

Question 27

What is generally the first type of antibody to be produced?

Answer 27

IgM

Question 28

What is one reason why B cells are specific to one antigen?

Answer 28

they only produce one type of B cell receptor